Radiator Fan on the way out?

[94-302-vert]

Looking for experience here...

Yesterday I had to run an errand (1 hour round trip car never got turned off). On the way back home I notice the car is running hot (dummy gage). It is running near the A in NORMAL... It is 65' out so not hot at all and I am doing about 50mph in 5th... so like 1700 rpm...

I turn on the A/C to get the high speed fan on, car cools to the O/R in NORMAL where it usually runs. Seems to indicate the low speed fan is not working.

Get home I check for water in the oil and oil in the coolant. Both look OK. So good here. Plug and unplug the fan since I just did the radiator 2 weeks and 1k miles ago.

This morning it is 60" out. I leave for work and I am paranoid watching the gage. I see the gage rise then fall when the Tstat opens (rise to R then fall ot N/O). then for the next 10-15 miles it runs normal tems (O/R). After that it starts to heat up again. Again turning on the A/C cools the car.

So is my fan going out or maybe the connector for it. What is everyone's thoughts. I want to try and figure this otu today as I would rather not install a manual fan switch as I plan to get a twEECer this winter where I can monitor my actual temps and adjsut my fan speed.

THANKS!!!

 

[BlownFiveLiter]

Apply 12v to pin 14 of the CCRM to see if the low speed fan comes on. If not, I'd say it could definitely be on its way out. If you need/want to test the high speed, ground pin 17 (just don't keep the 12v on pin 14 while doing that).

 

[94-302-vert]

Thanks Matt.

Does anyone know what the pinout is at the fan? I think I want to try this as well as monitor the voltage being applied to the fan. I am thinking that one is ground then one is a positive (12V) for the low speed and one is for the high speed posiitve (12V)?

 

[HISSIN50]

Thanks Matt.

Does anyone know what the pinout is at the fan? I think I want to try this as well as monitor the voltage being applied to the fan. I am thinking that one is ground then one is a positive (12V) for the low speed and one is for the high speed posiitve (12V)?

Viewed from the bottom of the hood (where your head is when looking down), the top fan wire is ground, middle is low and bottom is high speed as I recall.

See the bolded part of this tech note named: If a car runs hot at slow speeds or while stationary, but cools well at speed (40 mph +).

A lot of it you know or doesn't apply, but it in case the background info helps (there's a link for checking the EDF relay and CCRM pin switches that Matt mentioned).

You might find you have an ECT issue. If it's ok, but Pin 14 never sees 12 volts at 208*F+, consider a bad PCM driver.

FWIW, I'd still consider doing the manual switches. You dont want to play games here, and even with the RT, if an issue arises, it's nice to be able to flip the fan on.

Good luck Chris.

 

[94-302-vert]

Thanks for the links Hissin.

I am probably going to do some diagnostics over the next couple of days and then I may even just wire a t-stat to switch the high speed fan rather than doing anything with the low speed (assuming it even works).